Watches and clocks driven by a stepping motor in response to signals from a frequency-stabilized oscillator, especially one of the crystal-controlled type, tend to keep time with great precision over a period of many months. There is, generally, no need for resetting the hands of the timepiece except when it becomes necessary to replace a spent battery. It is therefore not unusual, especially with traveling clocks, to make a resetting knob of a high-precision timepiece accessible only upon removal of a lid overlying a battery compartment, thereby preventing any undesired change in the position of the clock hands.
Still, a changeover from standard to daylight-saving time or vice versa may call for an out-of-turn readjustment by one full hour; such adjustment, by one or more hours, may also be required when the user travels from one time zone to another.
The readjustment of a timepiece by a given number of hours is, of course, possible through manipulation of the resetting knob referred to. This operation, however, is not only inconvenient but liable to impair the accuracy of the current time indication by accidentally modifying the position of the minute hand. It has, therefore, already been proposed to provide a clockwork with two separate setting members engaging respective gears which are coupled to each other by a friction clutch, rotation of one of these members resetting both the minute and hour hands while rotation of the other member resets only the hour hand; see German laid-open application No. 2,828,996 published Apr. 17, 1980. The clutch disclosed in that German publication also provides 12 distinct relative angular positions between a minute shaft and an hour shaft in which they are yieldably indexed.